Macerate the strawberries: add the diced strawberries, maple syrup, vanilla, and salt to a small bowl. Stir and let sit 10 to 15 minutes while you make the mug cake, until the berries release their juices.
Lightly grease a 12 to 14 ounce microwave-safe mug.
Add the flour, coconut sugar, baking powder, and salt to the mug. Whisk with a fork until evenly combined.
Add the melted butter, milk, Greek yogurt, vanilla, and almond extract. Stir just until a thick, smooth batter forms. Do not overmix.
Smooth the top of the batter. Microwave 60 to 75 seconds, starting at 60. The top should look set but still feel soft when gently pressed.
Let the mug cake cool for 2 minutes.
Poke 4 to 5 holes into the top of the warm cake with a toothpick or skewer.
Spoon 1 to 2 teaspoons of the strawberry juice over the cake and let it soak in for about 30 seconds.
Pile the macerated strawberries over the top.
Finish with whipped cream and a fresh strawberry.